This invention relates to a measurement system for the alignment and measurement of positions with a tachymeter when the geodetic coordinates of these positions are known.
Beginning at a known position, the coordinates of this position are transposed to the terrain as orthogonal coordinates (x,y, or .DELTA.x, .DELTA.y respectively) or as polar coordinates (.alpha.,e) and the individual point is located in the terrain. Here the optical training on the known position is effected by the measuring assistant with the use of visual or oral signals. At large distances or in noisy locations, radio may be used for better communication. It is also feasible to process this measurement by means of a tachymeter at the location to be aligned. It is very difficult in this case to direct the measuring assistant, since the result of the measurement at the location of the tachymeter cannot be recognized at the location of the reflector, and even an experienced measuring assistant might make some motions between the order from the known location and the conscious execution thereof. This has a deleterious influence upon the exact locating of the individual positions.
The invention is therefore directed to the exact determination of the deviation of an aligned or measured location from its desired position, and to the provision of means for making this deviation immediately visible to the measuring assistant. The invention is also directed to improving communication between the point having a known position, and the point to be aligned, as well as the improvement of accuracy of measurement and alignment and simultaneously a decrease of time spent for these activities. The invention is also directed to assuring the communication of the deviation to the measuring assistant under all circumstances.
Briefly stated, according to the invention, an electronic tachymeter is positioned at the known location. The tachymeter transmits electromagnetic radiation to a reflector adapted to be trained upon the point to be aligned. Radiation reflected from the reflector is received and employed for the determination of distance and direction. The tachymeter system incorporates a calculator, a modulator and a transmitter; the reflector system incorporates a receiver, a demodulator (pulse integrator), an evaluating and storage unit and a display unit. The computer may be a component of the electronic tachymeter. It calculates the differences of the coordinates (.DELTA.x, .DELTA.y, or .alpha.,e respectively) which indicate how far the reflector must be moved, in order to locate it at the position of alignment according to known formulae. The computer may be capable, of course, of executing additional calculating operations, needed for the distance and direction processes, but which are not necessary for this invention.
The modulator is usually not identical with modulators conventionally used for distance measurements. The modulator serves to convert the digital signals received from the computer into a transmittable analog mode. Modulation may be executed according to amplitude, frequency, phase or any other known method of modulation.
The transmitter is of conventional construction. According to one very simple embodiment, it is comprised of a loudspeaker and a hand-held transceiver, whose loudspeaker is coupled to the first mentioned loudspeaker. The transceiver transmits radio signals corresponding to the output signals of the modulator.
The receiver at the reflector may, in its simplest embodiment, also consist again of a hand-held transceiver having its loudspeaker coupled to a microphone. Both transceivers serve to receive or transmit acoustic signals of different frequency and to convert them to or from radio signals, respectively.
The demodulator digitalizes the signals received by the receiver and transmits them to an evaluating and storage unit, which prepares the signals for the display and transmits them to the display unit.
The computer, modulator and transmitter may also be combined in one computing and transmitting unit and may be located at an evaluating station, separated from both the tachymeter and reflector.
The computer may be a component of the tachymeter, and may consist of a central processing unit, a temporary storage, a receiving and transmitting unit, and a program storage.